Boosted Board V1 Battery Rebuild - Under $70

My brother asked me, "Hey, do you want a free Boosted Board that doesn't work anymore?" Of course the practical side of me said, "do I really have time for another project?" but the tinkerer side of me said "of course you do you ninny, it's a free BOOSTED board!!"

So ends that part of the story, I got a free electric longboard that was no longer very electric and I set about trying to fix it on a ultra-low budget. So, before we get too deep into this process I want to make this very clear I only temporarily fixed the longboard and I need to do some more work to get it to work perfectly.

I am going to go through the process I went through to get the board up and running again and at the end I am going to talk about what I plan on doing to hopefully fix it permanently. Okay, let's crack this thing open!

Dang the battery case is glued in there tight! I first had to remove the screws holding the battery to the board. I then had to snip the main power wires and sense wires going to the ESC. Try to leave these long enough to solder something to them later down the road. After that you need to remove the small Philips head screws attaching the back plate of the battery case to the actual case. Then I used a heat gun to warm up the glue connecting the back plate to the battery case and used a flat head screw driver to pry it up. This worked almost perfectly... almost.

Like I said... almost. The top piece of the back plate where the wires pass through was really stuck on there and ended up cracking while I pried it up. Nothing a bit of hot glue can't solve!

Okay, so the V1 Boosted Board battery uses A123 batteries. I was able to find a pretty decent deal for 12 new cells on ebay. After shipping they totaled up to $58 and arrived in a few days from CT. I checked each cell with a multimeter and then started to figure out how they were going to go into the original case. It would have been nice if they all would have just popped right into the case nice and neat but I don't have a spot welder so solder was going to be my only option (more on this later). This meant that things were not going to fit all nice nice in there and I needed to make some room by using a dremel with grinding wheel to remove some of the plastic bits inside the case.

Like I said, I had to use solder to make my connections and this worked... somewhat. The problem is that even after lightly sanding the tops of the batteries and applying solder paste the darn solder didn't want to stick nice to the batteries. I didn't want to over heat the cells and since they had to sit in series (+ side to - side) it was near impossible to get it all to link up neatly without becoming so cumbersome that they wouldn't fit back in the case. I used some super flexible silicon wire to make my connections and then hot glued the cells to each other for additional connection (which caused some trouble as you will see). I made sure to connect each of the cells to their proper location on the BMS. C1 would connect to the first cell, C2 to the second and so on. Don't mix these up unless you want to see magic smoke come out of your BMS.

With the hot glue placed around the batteries things got a bit dicey. They were too thick to neatly fit in the case and there was a lot of pressure on the cells to keep them stuck in there, this led to some issues later on which I will explain.

I decided to make things easy to remove and change by using XT-60 connectors to connect the batteries and the sense wires to the ESC. I simply soldered on some male connectors to them both (making sure to keep the polarity correct). I then soldered on the female ends to the battery case, plugged it all in and then....

NOTHING!

Yup, nothing. I got a fast blinking red light on the battery case which was what I had when I started. So I decided to plug in the charger and got a similar result. Nothing, nothing, nothing, definitely a bit frustrating to say the least.

A quick search online and I found out that the BMS needs to be reset by putting the longboard on a treadmill (who knew there was actually a use for treadmills?). Alas, I don't own a treadmill, but I sure do have a stationary belt sander!

I took the belt off the sander, placed the board between a scrap wood sandwich and then set it up so the rear wheels sat on the drive side of the sander. I used a 50# bag of salt to hold down the whole rig and fired it up. I ran the whole thing for about two minutes and then checked the battery (which I left connected with bungee cords to hold it to the board). Still red blinking after two minutes. I checked it again a couple of minutes later and got a solid green light! We were back in business.

So my XT-60s are great for quick connecting and disconnecting things (which the V1 Boosted board doesn't have... what were they thinking?) but the problem is that the connectors are bulky. I decided to make a collar to help connect things to the board and make room for the connectors. Yes, I used wood, not slick aluminum or plastic. I didn't want to invest myself deep into this without knowing how things were going to work. I figured I could go back and change materials after using this as a template / prototype. The collar literally fits around the base of the battery and allows for an secondary battery to be connected in parallel for a longer range (see the pic of the XT sticking out of the wood collar). It also allows for the other connectors to sit comfortably under the current battery pack. To connect the whole thing I had to make some longer screws that fit the current threads of the inset nuts in the board. I used a cutoff grinder to cut the machine screws to the correct length and then fit the whole thing to the board.

Before I screwed it down I made sure all the connections worked fine. I had to make a "Y" cable to run a secondary pack in parallel when I want to get a further range. You can see in the pics here a bit more detail on how I set that female end into place. I think the pictures explain the whole thing neatly but don't hesitate to reach out with any questions.

I ran a new XT60 to charge the board since the original barrel connector was fried (that might have been my fault, but I am not so sure). I put the XT connector right where the barrel connector was. I will need to make a little waterproof cover for this thing so I don't destroy my battery, but once again, we are just prototyping here.

Before I did a final close up on things I decided to check each battery as they were being charged. I used my ancient power supply to charge things super slow and low at 1amp. I then checked how each battery was taking a charge by writing down the voltage as it was charged to make sure the BMS was doing its thing. The batteries did a nice job taking a charge and everything seemed find and dandy, so...

Man oh man does this thing rip! You can get up to 20mph in a blink, what a blast!

So, here's the rub, it worked but not for super long. The problem was that, like I said earlier, the batteries really didn't want to hold the solder and I didn't want to overheat them so my connections were poor. With too much flex on the board one of the cells disconnect and the BMS goes back to flashing red! As soon as I let go of the board and push the power button again it all works fine. I guess my kids could use it but it's a bit of a powerhouse for a 10 and 7 year old. All is not lost though, I now know that I can fix this thing but I need better connections at the battery joints. Solder doesn't work in this case due to the series wiring I have to do and the tight confines of the battery case. We need to use a spot welder and some copper or nickel stripping!!

I don't own a spot welder but I found this fantastically simple version of a spot welder that I am in the process of piecing together. Next steps will be to disassemble the battery (big frowny face there) and start from the ground up. I might even make my own battery box on the ole 3D printer.

I hope that this gave you some inspiration to fix that busted Boosted Board (I love alliterations!) and please don't hesitate to reach out. I'll hopefully post the new build on this or another instructable.

Happy building and fixing!!